Apocrenic Acid (Humic Acid, Ulmic Acid) is one of the products of the natural decay of wood or other plant textures, and is found where woody fibre is decomposing in soils. It is soluble in water, and is an intermediate step in the assimilation by living plants of dead vegetable matter.
Apocrenic Acid
Chambers's Encyclopaedia, Volume 1: A to Beaufort
Source scan(s): p. 0353